This one is an interesting card overall, but it wont be played immediately in many decks as it is a bit restrictive
Molten Destruction
Basically, you grant the turns Energy to Feebas first, and then in the very next turn, you evolve into Milotic and use its ability and the turns Energy to give it all it needs to attack right away
Then, select the deck you want to personalize, and when editing that deck, go to More Details, to the right: Notice that sometimes you may miss and to the Sideboard (which is right above More Options), but what youre looking for is the screen shown below: Within a deck's details, you can set individual preferences for companions, sleeves and avatars for when you play that deck
In my blackwork piece, we incorporated intricate filigree and a delicate feather design, which you can see clearly in the close-up images
You may pay optional additional costs, such as kicker, and if there are any mandatory additional costs, those must be paid to cast the spell